Decompression Surgery was not successful - his syrinx is back :(

It is not what we had expected.  After his surgery in 2014 we thought we were all done with this. We thought we were out of the woods and moving on. It turns out that he most likely has other medical issues contributing to the brain malformation which were not known at the time of surgery.

In my previous post I wrote that his syrinx (the bubble in his spinal cord) was smaller 1 year post-op. Now, almost 2 years post op it is bigger. Additionally, his odontoid is now retroflexed which means that it is squeezing his brain stem (yellow circle in first image). The reason for the curved odontoid most likely is that he has joint hypermobility, diagnosed later by genetics.  This is where it gets tricky. He was diagnosed with Noonan Syndrome on August 24, 2014. People with Noonan syndrome can have joint hypermobility that looks a lot like Ehler-Danlos Syndrome 3 (EDS3).  On September 3, 2014 he had posterior fossa decompression surgery with C1 and C2 laminectomy (the bony arches of his top two vertebrae were removed) to make room for his brain.  The thing to note here is that when people with EDS3 have decompression surgery, they also have fusion surgery to stabililize the area. We did not know of the hypermobility when the surgery was done, had we known, the surgeon might not have removed C2?  Decompression surgery is a relatively easy procedure so it is the first surgery of choice for chiari malformation. However, for patients with hypermobility it can open up a whole new can of worms...it can lead to craniocervical instability.

Fast forward to today. What next?  He needs to have a flex-ex dynamic MRI which means they move his head into different positions during the MRI to see how much the odontoid really is pushing on his brain stem.  Then we need to discuss the type of surgery needed. Most likely it is a fusion of his skull to his spine, they do this with plates and screws.  After surgery some mobility is lost but hopefully not too much :(   But, first up is an ophthalmology appointment next week to check on his optic nerve.  Since he has daily headaches, the concern is that he has elevated intra cranial pressure due to the CSF blockage in his spinal canal.  A swollen optic nerve is a sign of elevated pressure. Then in a couple of months another consultation with genetics.

And that is the situation.  We are grateful to be living in the US where there are many "complex chiari" experts and these medical issues are well known.  People come from all over the world for this type of surgery. All we can do now is move on....and educate and advocate!!

MRI - June 2015 - syrinx measures 9mm by 45mm

MRI - May 2016 - odontoid pressing on the brainstem is circled in yellow. Syrinx measures 11mm by 59mm

Posterior Fossa Decompression Surgery

Now that we have decided on the neurosurgeon to perform the surgery we can focus more on the details of the procedure.  As an interesting side note, the neurologist noticed something on Auggie's MRI from when he was 6 months old - a large vein that is in the very back of the brain (straight sinus - the dark line you see here towards the back of the skull) was almost vertical and is usually at more of an angle - he said that this is sometimes an early indicator of chiari malformation.  We were not told anything about this at the time. 

Here's the MRI from May 2014 that shows the chiari malformation and syrinx. In this image you can see that part of his brain is squeezing down into his spinal canal resulting in a syrinx (light colored bubble in his spine):

As for the surgery itself, the neurosurgeon will shave off part of the bone in the back of the skull in addition to the fourth vertebrae to make room for the brain to move up, then he will probably shrink the bag around the cerebellar tonsils to make them move up into the brain more.  Finally he grafts the dura with Durepair and seals it with Tisseel.  The hope is that there is no CSF leakage or infection.  Other complications include blood loss.  Auggie will spend one night in the ICU followed by about 3 nights in a hospital room.  Full recovery takes about 6 weeks and we return for a follow-up about 2-3 weeks after discharge.  A follow-up MRI is done 3 months after surgery.  I will post more details as we get closer to surgery.

Chiari malformation with syringomyelia

There has been a major development here.  About 3 weeks ago Auggie slipped on wet concrete and hit his head hard.  He seemed fine for a few days but then on day 5 his head looked swollen and he seemed really out of sorts.  We had been in touch on the phone with the pediatrician but she had reassured us that as long as he wasn't vomiting we needn't worry.  That all changed when we brought him in on day 5 - she told us to get him to Children's Hospital ASAP. A CT scan confimed a fracture and heavy bleeding above the skull as well as an epidural hematoma in the brain.  He was checked in for observation and listed in serious condition - that night in the ICU was one of the hardest nights of my life - I didn't eat or sleep for 24 hours. 

The next day an MRI showed that the bleeding had slowed BUT it also showed that he had a malformation in his brain - the back of the brain was herniated and pushing down into his spinal column - the technical term is chiari malformation.  This malformation was an incidental finding and had been there all along - not since birth though - an MRI when he was 6 months did not show the malformation.  In addition, the MRI showed that he has 2 large cysts in his spinal canal that have formed due to fluid getting backed up around the herniated cerebellar tonsils.

After consulting with the neurosurgeon we were told that the pressure that the herniated tonsils and the cysts put on the spine can lead to paralysis if left untreated.  As it is, the malformation may be what is currently responsible for his difficulty with eating and drinking and his quick gag reflex that often leads to vomiting once he starts gagging.  We are told that it is a good thing it was discovered now and not later when it could have caused irreversible spinal cord damage, but we are not excited about the looming brain surgery.

The surgery (a procedure known as posterior fossa decompression surgery) to correct this problem entails opening and cutting away a piece of the skull and vertebrae, opening the dura (duraplasty) and patching it to give the brain more room, and if needed shrinking the cerebellar tonsils by cauderizing them - that part of the brain we are told has no function (you would hope). Then after 4-6 hours of surgery he will be in the hospital for 3-5 days.  The complications include infection and leaking of fluid from the patch - both potentially life threatening. The surgery itself does not address the cysts, but rather the cause of the cysts (the herniated cerebellar tonsils, which in his case push down 2 cm below the point where they should stop)  The hope is that the cysts disappear after surgery as the flow of fluid becomes smoother around the back of the brain.  An MRI to check this is done 6 months after surgery. If the cysts do not go away, then a second surgery is required to drain (shunt) the cysts - form what I have heard this operation is far more risky and complicated.

So far we have consulted with two neurosurgeons and we have a third appointment next week. So far they have both agreed that surgery can wait until August as he is not showing worsening symptoms at this time. To complicate the matter we have also found out that Auggie has some sort of clotting disorder and we are working with a hematologist to pinpoint it so that we can address it before surgery.  He is currently taking vitamin k before we have his PTT levels tested again next week.   I will be posting updates on this issue as we find out more....